Japan has confirmed its support for the United Nations to begin a Commission of Inquiry into crimes against humanity in North Korea.

Under the inquiry, a detailed investigation would be launched into human rights violations by the North Korean regime, both domestically and abroad.

Earlier this month, Human Rights Watch sent a letter to Japan's prime minister, Shinzo Abe, urging Tokyo to commit to the inquiry.

At a January 25 cabinet meeting, Japan's government confirmed it would begin negotiating with other governments on the establishment of the inquiry, with a proposal to be submitted to the UN after February 2013.

Human Rights Watch Japan director, Kanae Doi, told Radio Australia's Asia Pacific the human rights record of North Korea is "one of the worst in the world."

"The new international inquiry is very important because although the human rights situation in North Korea has been abysmal...for a long time, but not enough attention has been given by the international community," Ms Doi said.

Ms Doi said Japan's government has an interest in the human rights abuses of North Korea, as North Korea's government has admitted abducting several Japanese nationals.

She said having a single UN Special Rapporteur - who is looking into North Korea's human rights abuses - is not enough.

"We're proposing a Commission of Inquiry which would give a team to the Special Rapporteur, who should be leading this investigation," she said.

"What we want is a really in-depth investigation which would give the comprehensive texture of the situation and then give voice to hundreds and thousands of victims of the violations by the North Korean government."

Ms Doi said it will not be necessary to enter North Korea as part of the inquiry, with thousands of escapees now living outside North Korea's borders.